/**
 * 最佳实践：
 * 尽可能避免实现定义的和未指定的行为，因为它是不可控的。
*/

#include <iostream>

int main() {
    // define an integer variable named x
    int x; // this variable is uninitialized because we haven't given it a value

    // print the value of x to the screen
    std::cout << x << '\n'; // who knows what we'll get, because x is uninitialized

    return 0;
}